Presently, the most popular standard or medium for storing audio data is CD-DA (CD-Digital Audio). In CD-DA, a 74-minute digital signal can be recorded on a disk having a diameter of 12 cm. Recently, however, audio data compression techniques such as MP3 (MPEG-1 Audio Layer-III), ATRAC3 (Adaptive Transform Acoustic Coding 3), and WMA (Windows Media Audio) have been developed, and more and more users have enjoyed music on their computers using audio data which has been compressed by such compression techniques. Such compression techniques have features to compress the capacity of CD-DA audio data to, for example, about 1/10, and to provide low degradation in sound quality. In terms of the recording time of music, CD-DA non-compressed audio data is limited to a capacity of about 74 minutes per disk, while compressed audio data can have a capacity of over 700 minutes per disk. The compressed audio data can be written to, for example, a Recordable CD (Recordable Compact Disc), and audio devices capable of playing back Recordable CDs having compressed audio data written thereto have been marketed.
As described above, when users enjoy music, she/he can use non-compressed audio data and compressed audio data. It is an object of the present invention to provide an audio device capable of making more effective use of non-compressed audio data and compressed audio data.